Converting from Number column removes the summaryType and SummaryRenderer and you cannot set a summary selecting from the properties.

Steps to reproduce the problem:

Create a new ExtJS 4.1 project.
Create a grid.
Apply Autocolumns in the grid with a store.
Add a summary feature to the grid.
Add summaryType sum and a summaryRenderer to the column that has an integer type.
Convert to Number column.
Convert to normal column.
summaryType and summaryRenderer properties are not in the property list for the column.

The result that was expected:

You should be able to have a column with all the properties.

The result that occurs instead:

Properties in the new column are missing.

HELPFUL INFORMATION

Screenshot, Project, or Video:

See video: https://docs.google.com/open?id=0B0ClmYxwWvBdVFRjODJsTDViak0
After converting summaryType and summaryRenderer are removed from the properties.